Within a signaling system 7 (SS7) network, the signaling connection control part (SCCP) protocol is used for accessing databases and other entities within the network. The SCCP protocol also provides an advanced addressing capability where a subsystem is represented as an array of digits known as a global title address. By utilizing global title address translation, the SS7 point code (PC) and subsystem number (SSN) of a final destination are not required to be known by the message originator. All the originator is required to know is the called party dialed digits and the address of a node that can perform the global title translation. Global title translation is commonly employed to locate databases that provide 800 number toll free and caller ID services within telecommunications networks. Depending on network topology, global title translation processing is typically performed at a signal transfer point (STP), a signaling gateway (SG), or a service control point (SCP) where one network makes an inter-connection to an adjacent network.
The addressing information used to facilitate message routing at the SCCP level commonly includes a destination point code, a subsystem number, and optionally a global title. If a destination PC and SSN are not specified in the SCCP portion of an SS7 message, global title translation may be used to resolve a global title address contained in the message to a destination point code and subsystem number or optionally another global title address. In an SCCP message, the called party address field contains a routing indicator to instruct network routing entities, such as STPs, to route on either point code and subsystem number or global title address. If the routing indicator identifies the message as requiring routing based on a global title address, the called party address is submitted for global title translation to produce a new destination address, which may be the local node or a different node in the network. In the case of an intermediate GTT, the receiving node may translate the global title address information in the message again.
Currently, there are two forms of GTT, intermediate and final GTT. Intermediate GTT involves performing GTT processing on a message at a first network node, such as an STP, and routing the translated message from the STP with the routing indicator set to route-on-gt for further GTT processing by a second network node. Final GTT involves performing GTT processing on an SCCP message at a first network node, such as an STP, and routing the translated message based upon point code-ssn to the appropriate destination or terminating network node, such as a database application. In both GT translation scenarios, there is a need to better discriminate both intermediate and final GTT based upon who is sending the message. Accordingly, there exists a long-felt need for improved methods and systems for global title translation in telecommunications networks.